人胎胸腺的组织发生

本文在光镜和电镜下研究50例人胎的胸腺。8(1/2)周胎胸腺尚未分小叶,也不能分辨皮质和髓质。12周胸腺间充质隔分隔小叶,同时髓质内可见胸腺小体。14～16周小叶数量增多,皮质分化出内、外二区。外皮质色浅系T淋巴细胞繁殖区。17～20周胸腺的发育已较完善。胎期胸腺间充质隔及皮髓交界区发现一些非上皮网状细胞和大量嗜酸髓细胞。

Histogenesis of the Human Thymus

Fifty eases of human fetal thymus were studied by means of LM and TEM. At the 8th gestational week the thymus was not yet subdivided into lobules, nor recognized the cortex and medulla. By 12th week the lobules separated by mesenchymal sepia were showed in thymut, meanwhile some Hassall's corpu- scles were found in the medulla. During the 14-16 weeks period the quantity of lobules is rncreased, the cortex differentiates into internal and external regions. Lightly stained external cortex was proliferative region of T lypmho- cytes. In the weeks 17-20 the development of thymus became more completed. In the mesenchymal sepia and cortico-medullary junctions some nonepithe- lial reticular cells and numerous eosinophilic myelocytes were presented during fetal life.